Lung Infection Pathology Flashcards
inflammatory response to bacteria
typically acute inflammation w/ PMNs in alveoli, RBCs in septae
inflammatory response to viruses
chronic, lymphos in septae
inflammatory response to fungi and mycobacteria
granulomas- Langhans giant cells and histiocytes (connective tissue macrophage)
often have necrotic center
differentiate broncho and lobar pneumonia
broncho- scatter foci in single or multiple lobes, terminally ill pts, common cause of death, any type of bacteria
lobar- complete consolidation of lobe, usually strep pneumo, red hepatization early and grey hepatization late
both are bacterial!
describe strep pneumo
encapsulated G+ diplococci, normal nasopharynx resident, often preceded by viral infection and/or altered bronchial secretions
contrast the early vs late pathology of pneumococcal pneumonia
early (3-4 days)- red hepatization, pulm edema, intra alveolar PMNs and RBCS
late (5-7 days)- gray hepatization, serum/ fibrinous exudates, intra alveolar organization, macrophages
anaerobic bacteria examples
streptococci, fusobacteria, baccteroides
characteristic of anaerobic aspiration pneumonia
necrosis w/ or w/o abscess, foul smelling sputum
characteristics of actinomyces
abscesses w/ colonies (sulfur granules), not acid fast
characteristics of nocardia
absecess in immunocompromised, acid fast (to distinguish from actinomyces)
complication of bacterial pneumonia
abscess, pyothorax, empyema, bacteremia
describe a pulm abscess
walled off infection, foul sputum, commonly predisposed by alcoholism (more oral bacteria, impaired cough)
empyema
infection of pleural fluid, can become loculated
bacteremia
bacteria in the blood stream- endocarditis, meningitis, pericarditis
describe mycoplasma infection
acute inflammation in wall and lumen of bronchiole
milder (walking)
highly transmissible via droplets, easily treated
culture for MTB
small, acid fast bacillus
slow growing, 3-6 weeks
radiology findings for MTB
Gohn complex, nodules, cavities
ghon complex
combo of peripheral nidus of infection (ghon focus, often caseous necrosis) and an infected lymph node (hilar or mediastinal)
primary Tb
inhalation of MTB, granulomatous host response
most are asymptomatic
secondary Tb
new infection in previously sensitized pt or reactivation of primary TB (w/ lower immune response)
granulomas in apical/posterior upper lobes
multi possibilities: confined in granuloma or new granulomas, cavitate, disseminate thru miliary spread
4 complications of TB
miliary TB, hemoptysis (erosion into pulm artery), broncho pleural fistula (erosion into pleural space and empyema), cavity (future home for aspergilloma)
miliary TB
many small granulomas in multi organs from hematogenous spread
4 fungal pathogens and their locations
histo - ohio river valley, bird droppings
coccidiodies- SW US
crypto- pigeon droppings
blasto- mississippe, ohio, missouri rivers
histo immune response
necrotizing granulomatous inflammation- identicle to TB w/o silver stains
histology and gross of crypto
looks like a neoplasm grossly (and imaging), caseating granuloma, organisms visible w/ mucicarmine stain
shape of aspergillus
septate hyphae w/ acute angle branching
aspergillosis disease
invasive, aspergilloma, allergic bronchopulmonary aspergillosis (ABPA)
invasive aspergillosis
immunocompromised hosts- invasion of blood vessels and causes infarction/thrombosis
necrosis w/ organisms in vessel walls
aspergilloma
fungus ball (mycetoma)- grows w/i preexsiting cavity usually from TB
tangled mat of hyphae, visible by X ray
ABPA
immune reaction to aspergillus
eosinophilia of blood and sputum, increased igE
pneumocystis patholgy
filling of alveolar airspace w/ organisms and proteinaceous fluid- “frothy” exudates in alveoli
esp HIV pts
staining for PJP
silver stain shows cup shaped bugs
CMV histology
large cells w/ intranuclear inclusions
herpes histology for pulm
large cells w/ nuclear inclusions
3 Ms- mult nucleation, margination, molding (fusing together)
